I made my own new ground wires. Let me esimate the cost, I got 10ft of 8AWG monster cable wire for like $.75/ft at Tweeter, gold ring connectors were like $1.50 each. So realistically it took me say 4 ft tops of wire for new grounds so thats $3, and 4 ring connectors were $6 then. So under $10 to make my own. You could crimp your connectors on but I crimped and soldered mine and heat shrinked them, but the connectors came with the heat shrink. So those kits are worth about $10.

Also if you car is old like mine your ground wires are all gross and corroded so new weather proof wires are .